Lethal Emotions in Birds

[Chmeee]

I was wondering if strong emotions could kill birds.
My friend had a chocoyo (a type of parakeet) as a pet in his house, and every time a flock of chocoyos would fly by (he lives in the tropics) it would answer them. After a few weeks it died for no apparent reason, (it was fed well, no obvious symptoms of disease, etc) and someone said that it had died of sadness. This seemed really far fetched to me, but I have heard that birds have short, intense emotions.
Also, there is a mith(?) that I have heard several times that chickens can die of fright (overdose of adrenaline perhaps?).
If I haven't made it clear yet, this isn't an area of expertise for me, so I was hoping someone else could possibly shed some light.

[AstusAleator]

stress, adrenaline, etc, these things can break down cardiovascular tissue. Perhaps the bird had some sort of hormonal or stress response to the migration instinct, leading to a weakening of its body.
Did it stop eating? I probably don't know any more than you about birds, but it can't hurt to throw out hypotheses. Maybe the migratory instinct caused it to shift its eating pattern.